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PURPOSE OF REVIEW: The current review highlights advances in the use of direct-acting antiviral (DAA) agents in the treatment of hepatitis C virus (HCV) in chronic kidney disease (CKD) stages G4-5, end-stage renal disease, and kidney transplantation. The use of DAA to facilitate kidney transplantation of HCV negative recipients with kidneys from HCV-infected donors and in the management of HCV-related cryoglobulinemia are also reviewed. RECENT FINDINGS: DAA treatment results in rates of viral clearance (sustained virological response or SVR) of 90-100% in all studied CKD populations, comparable to SVR rates in the general population. DAA treatment allows safe and effective transplantation of HCV viremic kidneys into uninfected recipients. SUMMARY: The high SVR results achieved with DAA allow successful treatment of previously under-treated CKD populations, and encouraged innovative interventions such as the use of HCV-infected donor kidneys to uninfected kidney transplant recipients.
Subject(s)
Hepatitis C, Chronic , Hepatitis C , Renal Insufficiency, Chronic , Antiviral Agents/therapeutic use , Hepacivirus , Hepatitis C/complications , Hepatitis C/diagnosis , Hepatitis C/drug therapy , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/drug therapy , Humans , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/drug therapyABSTRACT
Plasma cell dyscrasias, including multiple myeloma (MM), are associated with diverse forms of pathology in the kidney. Some pathologic lesions, including light chain (myeloma) cast nephropathy (LCCN), are relatively common, while others, such as light chain proximal tubulopathy (LCPT), are less so. Both LCCN and LCPT are associated with clinical manifestations of acute kidney injury. Rare instances of coincidental LCPT and LCCN have been reported, but none to our knowledge of coincidental crystalline forms of these diseases, with similar forms appearing in the urine. While LCPT is usually associated with intracytoplasmic deposition of crystallized light chains, the intraluminal light chain casts in LCCN are typically amorphous and do not form crystals. We report here the co-occurrence of these two monoclonal crystalline forms of acute kidney injury in a 66-year-old woman with known history of κ-restricted multiple myeloma. Additionally, forms suggestive of a crystalline morphology were observed in the urine sediment. Clinicians who observe similar crystalline structures on renal biopsy or in urine sediment should have a high index of suspicion for underlying multiple myeloma as a unifying diagnosis.
Subject(s)
Acute Kidney Injury/complications , Immunoglobulin Light Chains/analysis , Kidney Tubules, Proximal/pathology , Multiple Myeloma/pathology , Aged , Crystallization , Female , Humans , Kidney Diseases/pathology , Multiple Myeloma/urine , Urine/cytologyABSTRACT
Leukocyte chemotactic factor 2 (LECT2) amyloidosis is a recently recognized entity that often affects the kidneys. Little information is available regarding kidney transplant outcomes in patients with LECT2 amyloidosis or who received kidney allografts containing LECT2 amyloid. We present clinical findings and allograft outcomes of 5 patients who received kidneys with donor-derived LECT2 amyloidosis. In all 5, LECT2 amyloidosis was discovered during protocol biopsies or in evaluation of suspected rejection. Less than 10% of kidney parenchyma was involved, with mostly interstitial and vascular deposits. Allograft function was not impaired and the amyloid deposits persisted for up to 8 years of follow-up. We conclude that kidneys with limited and localized LECT2 amyloid deposits that are otherwise suitable for transplantation need not be automatically discarded.
Subject(s)
Amyloidosis/diagnosis , Amyloidosis/genetics , Intercellular Signaling Peptides and Proteins/genetics , Kidney Transplantation/methods , Tissue Donors , Adult , Humans , Male , Middle Aged , Young AdultABSTRACT
We report the case of a 69-year-old man who presented with acute kidney injury in the setting of community-acquired Clostridium difficile-associated diarrhea and biopsy-proven acute oxalate nephropathy. We discuss potential mechanisms, including increased colonic permeability to oxalate. We conclude that C difficile-associated diarrhea is a potential cause of acute oxalate nephropathy.
Subject(s)
Calcium Oxalate/metabolism , Clostridioides difficile , Colon/metabolism , Diarrhea , Fluid Therapy/methods , Kidney Tubular Necrosis, Acute , Metronidazole/administration & dosage , Acute Disease , Aged , Anti-Infective Agents/administration & dosage , Biopsy , Clostridioides difficile/drug effects , Clostridioides difficile/isolation & purification , Diarrhea/complications , Diarrhea/microbiology , Diarrhea/physiopathology , Humans , Kidney/pathology , Kidney Function Tests , Kidney Tubular Necrosis, Acute/diagnosis , Kidney Tubular Necrosis, Acute/etiology , Kidney Tubular Necrosis, Acute/physiopathology , Kidney Tubular Necrosis, Acute/therapy , Male , Permeability , Probiotics/administration & dosage , Treatment OutcomeABSTRACT
BACKGROUND: Health behaviour adherence is associated with improved survival in kidney failure (KF); however, most patients with KF do not adhere to one or more health behaviours. Existing health behaviour interventions have significant limitations and do not focus on psychological factors that are associated with adherence and health. OBJECTIVES: To examine the feasibility, acceptability, and preliminary efficacy of a 12-week, phone-delivered, positive psychology-motivational interviewing (MI) intervention to promote psychological well-being and adherence in KF. DESIGN: Single-arm, proof-of-concept trial (N = 10). PARTICIPANTS: Participants were adults with KF undergoing haemodialysis and reporting suboptimal adherence to physical activity, diet, and/or medications. Participants attended weekly phone sessions with a study trainer, completed weekly positive psychology exercises (focused on gratitude, strengths, and meaning), and worked towards physical activity, diet, and/or medication goals. MEASUREMENTS: Feasibility was measured by the percentage of sessions completed, while acceptability was assessed through participant ratings of positive psychology and MI session ease and utility (0-10 Likert scales). We explored the intervention's impact on psychological outcomes and health behaviour adherence using validated scales and accelerometers. RESULTS: Participants completed 78% of sessions and rated the program's components as easy to complete (positive psychology: 8.7 ± 1.5; MI: 8.3 ± 2.0) and subjectively helpful (positive psychology: 8.8 ± 1.2; MI: 8.8 ± 1.6). The intervention led to promising but nonsignificant improvements in psychological and adherence measures. CONCLUSIONS: This 12-week, phone-delivered program was feasible, well-accepted, and associated with nonsignificant improvements health behaviour adherence, highlighting the need for a larger efficacy trial.
Subject(s)
Motivational Interviewing , Renal Insufficiency , Adult , Humans , Diet , Exercise/psychology , Feasibility Studies , Health Behavior , Proof of Concept StudyABSTRACT
Introduction: Cardiovascular disease is a significant cause of mortality after kidney transplantation. Whether pre-transplant screening for coronary artery disease (CAD) in asymptomatic kidney transplant candidates (KTCs) is beneficial is unclear. Methods: We conducted a retrospective cohort study evaluating post-transplant cardiovascular events in 192 high-risk KTCs who underwent pre-transplant CAD evaluation. The study aimed to identify risk factors associated with finding severe CAD on pre-transplant angiography, and to assess the relationship between screening strategies and post-transplant cardiovascular events. Results: At five years post-transplant, cardiovascular events occurred in 23.9% of subjects. Prior CAD history and left ventricular ejection fraction (LVEF) < 50% were associated with higher odds of finding severe CAD on pre-transplant angiography. Severe CAD on angiography was associated with a higher risk of early cardiovascular events within six months of transplantation. However, coronary intervention in KTCs with severe CAD was not associated with lower rates of post-transplant cardiovascular events. Conclusion: Pre-transplant coronary angiography to identify severe CAD is of highest yield in KTCs with a history of CAD or an LVEF < 50%. Our findings indicate that the identification of severe CAD in KTCs has prognostic significance for the early post-transplant period. Optimization of medical therapy in these high-risk KTCs may improve post-transplant cardiovascular outcomes.
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BACKGROUND: Kidney failure (KF) is associated with impaired physical function, reduced health-related quality of life, increased health care costs, and high rates of cardiovascular complications and mortality. Among individuals with KF, well-being and related constructs, such as positive affect, optimism, self-efficacy, and resilience, may have both mental and physical health benefits, independent of the effects of negative emotions and affective syndromes. However, there has been minimal review of these characteristics in people with KF. OBJECTIVE: We conducted a scoping review, using a semi-systematic approach, to summarize the relationships between well-being characteristics and renal health, the potential mechanisms mediating these relationships, and the effects of interventions that promote positive constructs on adherence and health outcomes. METHODS: We conducted database searches using PubMed and PsycINFO until November 2020. Articles were included if they examined (1) relationships between a well-being construct and health outcome in patients with KF, (2) potential biologic or behavioral mediators, or (3) interventions that target positive psychologic constructs as outcomes or mediators in KF and (4) were written in English or Spanish. RESULTS: Among patients with KF, well-being constructs are associated with increased health-related quality of life, reduced morbidity and complications, and increased survival. Potential mechanisms mediating these associations include reduced inflammation, improved autonomic and endothelial function, and improved health behavior adherence. Psychologic and psychosocial interventions promoting well-being have primarily focused on improving self-efficacy to promote behavior change, with limited study of interventions to promote positive psychologic constructs in this population. CONCLUSIONS: Further research is needed to better understand the relationship between well-being constructs and health, specific to KF populations. This could inform the development of needed interventions that harness the promotion of other positive characteristics to improve well-being and health.
Subject(s)
Quality of Life , Renal Insufficiency , Health Behavior , Humans , Optimism , Self EfficacyABSTRACT
Patients with end-stage renal disease (ESRD) are often excluded from potentially curative allogeneic hematopoietic cell transplantation (alloHCT). Our institution pioneered simultaneous living donor kidney transplantation in patients undergoing alloHCT from the same donor for hematologic malignancies. Herein, we present the case of a 31-year-old woman diagnosed with myelodysplastic syndrome who developed ESRD during cytoreductive induction therapy. She achieved disease control, then successfully underwent a human leukocyte antigen (HLA)-haploidentical alloHCT while on hemodialysis. After rapidly tapering off graft-versus-host disease prophylaxis, fourteen months from her alloHCT she received a kidney transplant from her same haploidentical sibling donor, which obviated the need for further systemic immunosuppression.
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Introduction: The kidney transplant recipient population in the United States is aging rapidly, which may exacerbate some of the limitations of conventional outcome metrics. Methods: Using data from the Scientific Registry of Transplant Recipients (SRTR), age-stratified unadjusted Kaplan-Meier and competing risk survival analyses were performed on a cohort of 238,123 adult recipients of a first-time single kidney transplant between 2000 and 2017. These were compared with a multistate model incorporating 5 post-transplant states (alive with functioning graft, death with functioning graft, graft failed (alive), retransplanted, and death after graft failure). Results: Kaplan-Meier resulted in an age-dependent overestimation of the risks of graft failure and death with functioning graft, compared with competing risk or multistate models. In elderly (≥75 years old) recipients, the absolute overestimation of the risk of death with functioning graft was 4-fold higher than in those younger than 55 years. The multistate model demonstrated that for patients transplanted at age 55 years and older, the probability of being back on dialysis was never more than 4% at any point post-transplant. The underlying reasons were low graft failure rates and high mortality after resuming dialysis as follows: 2-year mortality after graft failure was 38%, 54%, and 67% in recipients aged from 55 to 64 years, from 65 to 74 years, and those aged 75 years and older, versus 20% in those younger than 55 years. Conclusion: Multistate models provide an accurate and comprehensive assessment of the life course of kidney transplant recipients. This may be particularly relevant in older recipients, who are more prone to event rate overestimation and for whom outcomes after graft failure are substantially worse than for younger recipients.
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BACKGROUND: Borderline changes (BL) with stable renal function is a controversial category in renal transplantation, given its contradictory outcomes. The aim of this study was to compare the clinical outcomes of BL in patients with stable renal function classified as focal and diffuse according to the extent of tubulitis. METHODS: Patients with no history of rejection with a surveillance graft biopsy at 3 or 12 months showing BL (n = 40), acute cellular rejection (n = 20) or normal biopsies (n = 20), were included in this study. Biopsies with BL were divided into diffuse BL (BLD) and focal BL (BLF) according to the extent of tubulitis. Because of the low frequency of subclinical ACR (ACRND) (n = 12), biopsies with ACR and graft dysfunction (ACRD) (n = 8) were also included. A composite outcome that included the presence of rejection in subsequent biopsies, graft loss, patient death, decrease in GFR ≥30% or presence of de novo DSA (dnDSA) during the first year of follow-up was evaluated. RESULTS: The primary composite outcome occurred in five patients of each of the Normal, BLF and ACRND, eight patients with BLD and six patients with ACRD (p = 0.105). A trend towards more rejection episodes was observed in the ACRND and ACRD. Also, a shorter time to rejection in the BLD, ACRND and ACRD groups compared to BLF and Normal groups (p = 0.039) was observed. During the first year of follow-up, no patient in the ACRND group developed dnDSA, compared to 15-25% in the other groups. The median time of dnDSA development in the BLF group was 45 months, and in the BLD group was 10 months (p = 0.020). CONCLUSION: Classifying BL biopsies with stable renal function into focal and diffuse categories, is a simple and feasible strategy that helps to differentiate between BLD with a phenotype that shows a trend towards worse outcomes, and BLF that behaves more similar to normal biopsies.
Subject(s)
Kidney Transplantation , Biopsy , Graft Rejection/etiology , Graft Survival , Humans , Kidney/pathology , Kidney Transplantation/adverse effects , Retrospective StudiesABSTRACT
Gain-of-function polymorphisms in the transcription factor IFN regulatory factor 5 (IRF5) are associated with an increased risk of developing systemic lupus erythematosus. However, the IRF5-expressing cell type(s) responsible for lupus pathogenesis in vivo is not known. We now show that monoallelic IRF5 deficiency in B cells markedly reduced disease in a murine lupus model. In contrast, similar reduction of IRF5 expression in macrophages, monocytes, and neutrophils did not reduce disease severity. B cell receptor and TLR7 signaling synergized to promote IRF5 phosphorylation and increase IRF5 protein expression, with these processes being independently regulated. This synergy increased B cell-intrinsic IL-6 and TNF-α production, both key requirements for germinal center (GC) responses, with IL-6 and TNF-α production in vitro and in vivo being substantially lower with loss of 1 allele of IRF5. Mechanistically, TLR7-dependent IRF5 nuclear translocation was reduced in B cells from IRF5-heterozygous mice. In addition, we show in multiple lupus models that IRF5 expression was dynamically regulated in vivo with increased expression in GC B cells compared with non-GC B cells and with further sequential increases during progression to plasmablasts and long-lived plasma cells. Overall, a critical threshold level of IRF5 in B cells was required to promote disease in murine lupus.
Subject(s)
B-Lymphocytes/metabolism , Interferon Regulatory Factors , Interleukin-6/metabolism , Lupus Erythematosus, Systemic , Tumor Necrosis Factor-alpha/metabolism , Animals , Autoimmunity , Disease Models, Animal , Gain of Function Mutation , Gene Expression Regulation/immunology , Germinal Center , Interferon Regulatory Factors/deficiency , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Lupus Erythematosus, Systemic/genetics , Lupus Erythematosus, Systemic/immunology , Mice , Signal Transduction/immunologyABSTRACT
Reactivation of BK virus (BKV) remains a dreaded complication in immunosuppressed states. Conventionally, BKV is known as a cause for BKV-associated nephropathy and allograft dysfunction in kidney transplant recipients. However, emerging studies have shown its negative impact on native kidney function and patient survival in other transplants and its potential role in diseases such as cancer. Because BKV-associated nephropathy is driven by immunosuppression, reduction in the latter is a convenient standard of care. However, this strategy is risk prone due to the development of donor-specific antibodies affecting long-term allograft survival. Despite its pathogenic role, there is a distinct lack of effective anti-BKV therapeutics. This limitation combined with increased morbidity and health care cost of BKV-associated diseases add to the complexity of BKV management. While summarizing recent advances in the pathogenesis of BKV-associated nephropathy and its reactivation in other organ transplants, this review illustrates the limitations of current and emerging therapeutic options and provides a compelling argument for an effective targeted anti-BKV drug.
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Kidney transplantation (KT) is the most effective way to decrease the high morbidity and mortality of patients with end-stage renal disease. However, KT does not completely reverse the damage done by years of decreased kidney function and dialysis. Furthermore, new offending agents (in particular, immunosuppression) added in the post-transplant period increase the risk of complications. Cardiovascular (CV) disease, the leading cause of death in KT recipients, warrants pre-transplant screening based on risk factors. Nevertheless, the screening methods currently used have many shortcomings and a perfect screening modality does not exist. Risk factor modification in the pre- and post-transplant periods is of paramount importance to decrease the rate of CV complications post-transplant, either by lifestyle modification (for example, diet, exercise, and smoking cessation) or by pharmacological means (for example, statins, anti-hyperglycemics, and so on). Post-transplantation diabetes mellitus (PTDM) is a major contributor to mortality in this patient population. Although tacrolimus is a major contributor to PTDM development, changes in immunosuppression are limited by the higher risk of rejection with other agents. Immunosuppression has also been implicated in higher risk of malignancy; therefore, proper cancer screening is needed. Cancer immunotherapy is drastically changing the way certain types of cancer are treated in the general population; however, its use post-transplant is limited by the risk of allograft rejection. As expected, higher risk of infections is also encountered in transplant recipients. When caring for KT recipients, special attention is needed in screening methods, preventive measures, and treatment of infection with BK virus and cytomegalovirus. Hepatitis C virus infection is common in transplant candidates and in the deceased donor pool; however, newly developed direct-acting antivirals have been proven safe and effective in the pre- and post-transplant periods. The most important and recent developments on complications following KT are reviewed in this article.
Subject(s)
Cardiovascular Diseases/complications , Diabetes Mellitus , Hepatitis C, Chronic/complications , Kidney Transplantation , Antiviral Agents , Hepatitis C, Chronic/drug therapy , Humans , Immunotherapy , Kidney Failure, Chronic/surgery , Mortality , Neoplasms/complications , Neoplasms/prevention & control , Postoperative Complications , Risk Factors , Tacrolimus/adverse effects , Tacrolimus/therapeutic useABSTRACT
Hepatitis C virus (HCV) infection is prevalent in patients with kidney disease including transplant candidates and recipients. It is associated with increased morbidity and mortality in end-stage renal disease patients and also increases the risk of allograft rejection and decreases allograft and patient survival post-transplant. Newly developed direct acting antivirals have revolutionized the way HCV is treated. Whether patients are treated before or after kidney transplantation, the cure rates with direct acting antivirals are >90%. Great debate has formed revolving the optimal timing to treat kidney transplant candidates. On the one hand, treatment before transplantation decreases early post-transplant complications related to HCV. On the other, postponing treatment until after transplantation opens the possibility of transplanting a kidney from a HCV positive donor, which is associated with shorter waiting time and improved organ utilization by expanding the organ donor pool. Most patients living in an area where waiting time is reduced by accepting an HCV positive kidney would benefit by the strategy of treatment post-transplantation, but this decision needs to be individualized in a patient-by-patient basis given that there are special circumstances (i.e., severe HCV-related extrahepatic manifestations, availability of live donors, etc.) in which treatment before transplant might be preferred.
Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C, Chronic/therapy , Kidney Transplantation/adverse effects , Antiviral Agents/pharmacology , Female , Hepatitis C, Chronic/pathology , Humans , Kidney Transplantation/methods , MaleABSTRACT
Diabetic nephropathy, the leading cause of renal failure worldwide, affects approximately one-third of all people with diabetes. Microalbuminuria is considered the first sign and the best predictor of progression to renal failure and cardiovascular events. However, albuminuria has several limitations. Therefore, earlier, more sensitive and specific biomarkers with greater predictability are needed. The aim of this paper is to discuss the current literature on biomarkers of glomerular injury that have been implicated in diabetic kidney disease.
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BACKGROUND: Therapeutic hypothermia has been shown to reduce neurological morbidity and mortality in the setting of out-of-hospital cardiac arrest and may be beneficial following brain injury and cardiopulmonary bypass. We conducted a systematic review to ascertain the effect of therapeutic hypothermia on development of acute kidney injury (AKI) and mortality. METHODS: We searched for randomized controlled trials in MEDLINE through February 2011. We included trials comparing hypothermia to normothermia that reported kidney-related outcomes including, development of AKI, dialysis requirement, changes in serum creatinine, and mortality. We performed Peto fixed-effect and random-effects model meta-analyses, and meta-regressions. RESULTS: Nineteen trials reporting on 2218 patients were included; in the normothermia group, the weighted rate of AKI was 4.2%, dialysis requirement 3.7%, and mortality 10.8%. By meta-analysis, hypothermia was not associated with a lower odds of AKI (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.68, 1.51; P=0.95) or dialysis requirement (OR 0.81; 95% CI 0.30, 2.19; P=0.68); however, by meta-regression, a lower target cooling temperature was associated with a lower odds of AKI (P=0.01). Hypothermia was associated with lower mortality (OR 0.69; 95% CI 0.51, 0.92; P=0.01). CONCLUSIONS: In trials that ascertained kidney endpoints, therapeutic hypothermia prevented neither the development of AKI nor dialysis requirement, but was associated with lower mortality. Different definitions and rates of AKI, differences in mortality rates, and concerns about the optimal target cooling temperature preclude definitive conclusions.